Sirens not just used for tornadoes - Chicago News and Weather | FOX 32 News

Tornado sirens blared Sunday night in the southwest suburb of Homer Glenn, but FOX Chicago News has learned there were no tornadoes and no warnings.

The National Weather Service issued its last tornado warning at 5:25 pm. So what gives? The office of emergency management in Will County tells us it was a malfunction possibly caused by lightning.

And this isn't the first time Chicago residents have been left confused. Last year a siren snafu in DuPage County led to a new tornado siren policy. And a few years ago there was confusion during a tornado warning at Wrigley Field.

So how do you know what that siren really means? According to the John Von Thaden, the general manager of Federal Signal, the sirens are not only for tornadoes.

"Today they are not just used for weather alerts but for all hazard events. That can include projects or events on college campuses. In, addition they're used for flood or other flash warnings or other storms that might come through," Von Thaden said.

Sirens come in many sizes and shapes and they can be triggered via radio or even smart phone.

In Will, DuPage and Cook County sirens now sound for tornadoes and extreme, life threatening winds.

In the city of Chicago, warnings are centralized downtown and triggered for the various zones around the city. Their policy is to use sirens for any threat whether natural or manmade. However, the final decision of when and why to hit the trigger is based on human judgment and left to each community.